Weekly low-dose methotrexate therapy for cutaneous sarcoidosis. Hughes BR, Marks R, Pearse AD, et al. Methotrexate is the most effective systemic agent in psoriasis and has been used by dermatologists for more than 50 years. Various guidelines have been formulated in various countries for prescribing methotrexate, but there is no consensus statement on this issue. Methotrexate in psoriasis: Revised guidelines. J Eur Acad Dermatol Venereol 2011;25: Bishnoi, et al. Its efficacy in the treatment of severe or recalcitrant psoriasis unresponsive to topical therapy earned the drug a new indication in the 1950s (). In a preliminary study, Kozarek et al. Methotrexate in psoriasis: Revised guidelines.